Extreme ultraviolet (euv) exposure system and method of manufacturing semiconductor device using the same

ABSTRACT

An extreme ultraviolet (EUV) exposure system capable of improving the yield of an EUV exposure process by improving EUV exposure performance, and furthermore, capable of increasing throughput or productivity of the EUV exposure process, the EUV exposure system including an EUV exposure apparatus configured to perform EUV exposure on a wafer disposed on a chuck table, a load-lock chamber combined with the EUV exposure apparatus and configured to supply and discharge the wafer to/from the EUV exposure apparatus, and an ultraviolet (UV) exposure apparatus configured to perform UV exposure by irradiating an entire upper surface of the wafer with a UV light without using a mask.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of priority under 35 U.S.C §119 toKorean Patent Application No. 10-2016-0095487, filed on Jul. 27, 2016,in the Korean Intellectual Property Office, the disclosure of which isincorporated herein in its entirety by reference.

BACKGROUND

The present disclosure relates to an exposure system, for example, to anextreme ultraviolet (EUV) exposure system performing exposure by usingextreme ultraviolet (EUV) light.

Transmission-type exposure systems that use deep ultraviolet (DUV) lighthave been widely used as exposure apparatuses. As the integrationdensity of semiconductor devices has improved and line widths thereofhas decreased, next-generation lithography technologies have beenstudied to further improve the resolution of optical lithography. Amongthem, an extreme ultraviolet (EUV) exposure apparatus that uses EUVlight having a shorter wavelength than that of DUV light has beenactively developed and is being applied to semiconductor manufacturingprocesses. In this regard, EUV exposure may use slots with narrow widthsand may be performed with optical systems using a scan technology.Therefore, the EUV exposure apparatus may be referred to as a scanner.For example, fields may be scanned on a wafer one by one at a separatetime instead of exposing the entire wafer at the same time. The scanningmay be performed by simultaneously moving a wafer and a reticle andmoving the slots crossing fields.

SUMMARY

Aspects of the inventive concept provide an extreme ultraviolet (EUV)exposure system capable of improving the yield of an EUV exposureprocess by improving EUV exposure performance, and furthermore, capableof maintaining or increasing throughput or productivity of the EUVexposure process.

According to an aspect of the inventive concept, there is provided anEUV exposure system including an EUV exposure apparatus configured toperform EUV exposure on a wafer disposed on a chuck table, a load-lockchamber combined with the EUV exposure apparatus and configured tosupply and discharge the wafer to/from the EUV exposure apparatus, andan ultraviolet (UV) exposure apparatus configured to perform UV exposureby irradiating a UV light to an entire upper surface of the wafer,wherein the UV exposure apparatus does not include a mask holder.

According to another aspect of the inventive concept, there is providedan EUV exposure system including an EUV exposure apparatus configured toperform EUV exposure on a wafer disposed on a chuck table, a firstload-lock chamber combined with the EUV exposure apparatus andconfigured to supply the wafer into the EUV exposure apparatus, a secondload-lock chamber combined with the EUV exposure apparatus andconfigured to discharge the wafer from the EUV exposure apparatus tooutside of the EUV exposure apparatus, and a UV exposure apparatusdisposed in the EUV exposure apparatus or the second load-lock chamberand configured to perform UV exposure on the wafer.

According to an aspect of the present disclosure, an apparatus includes:an EUV exposure chamber comprising a chuck table, an extreme ultraviolet(EUV) light source configured to emit EUV light and a mask holder beingpositioned between the EUV light source and the chuck table; and anultraviolet (UV) light source configured to emit UV light, wherein theEUV light source is positioned to expose a photoresist (PR) layer coatedon a wafer to an EUV light emitted from the EUV light source that istransferred via a photomask held by the mask holder, and wherein the UVlight source is configured to expose the PR layer to a UV light emittedfrom the UV light source without using a photomask after the PR layer isexposed to the EUV light.

According to an aspect of the present disclosure, a method ofmanufacturing a semiconductor device includes steps of coating aphotoresist layer on an upper surface of a wafer, exposing thephotoresist layer to an extreme ultraviolet light reflected by aphotomask, exposing an entire upper surface of the wafer to anultraviolet light without using a photomask after exposing thephotoresist layer to the extreme violet light, and developing thephotoresist layer to form a photoresist pattern on the wafer afterexposing the entire upper surface of the wafer to the ultraviolet light.

BRIEF DESCRIPTION OF THE DRAWINGS

Example embodiments of the inventive concept will be more clearlyunderstood from the following detailed description taken in conjunctionwith the accompanying drawings in which:

FIG. 1 is a schematic block diagram of an extreme ultraviolet (EUV)exposure system according to an example embodiment of the inventiveconcept;

FIG. 2 is an exemplary schematic view of the EUV exposure system of FIG.1, according to an example embodiment of the inventive concept;

FIG. 3 is a schematic diagram of an example embodiment of forming anultraviolet (UV) exposure apparatus in an EUV exposure apparatus in theEUV exposure system of FIG. 2 according to an example embodiment of theinventive concept;

FIG. 4 is a detailed perspective view of the UV exposure apparatus ofFIG. 3;

FIGS. 5A and 5B are respectively a schematic cross-sectional view and aschematic plan view of an example embodiment of forming the UV exposureapparatus in a load-lock chamber in the EUV exposure system of FIG. 2;

FIG. 6 is a schematic cross-sectional view of an example embodiment offorming the UV exposure apparatus in the load-lock chamber in the EUVexposure system of FIG. 2;

FIG. 7 is a schematic view of the EUV exposure system of FIG. 1,according to an example embodiment of the inventive concept;

FIG. 8 is a graph illustrating a principle of improving the exposureperformance of EUV exposure systems according to example embodiments ofthe inventive concept;

FIG. 9 is a graph for comparing the exposure performance of EUV exposuresystems according to example embodiments of the inventive concept withthat of an existing EUV exposure system;

FIG. 10 is a flowchart of an EUV photolithography process according toan example embodiment of the inventive concept; and

FIG. 11 is a flowchart of a process of manufacturing a semiconductordevice through an EUV photolithography process according to an exampleembodiment of the inventive concept.

DETAILED DESCRIPTION

Hereinafter, the present disclosure will be described in detail withreference to the accompanying drawings, in which various embodiments areshown. The invention may, however, be embodied in many different formsand should not be construed as limited to the example embodiments setforth herein. These example embodiments are just that—examples—and manyimplementations and variations are possible that do not require thedetails provided herein. It should also be emphasized that thedisclosure provides details of alternative examples, but such listing ofalternatives is not exhaustive. Furthermore, any consistency of detailbetween various examples should not be interpreted as requiring suchdetail—it is impracticable to list every possible variation for everyfeature described herein. The language of the claims should bereferenced in determining the requirements of the invention.

In the drawings, like numbers refer to like elements throughout. Thoughthe different figures show various features of exemplary embodiments,these figures and their features are not necessarily intended to bemutually exclusive from each other. Rather, certain features depictedand described in a particular figure may also be implemented withembodiment(s) depicted in different figure(s), even if such acombination is not separately illustrated. Referencing suchfeatures/figures with different embodiment labels (e.g. “firstembodiment”) should not be interpreted as indicating certain features ofone embodiment are mutually exclusive of and are not intended to be usedwith another embodiment.

Unless the context indicates otherwise, the terms first, second, third,etc., are used as labels to distinguish one element, component, region,layer or section from another element, component, region, layer orsection (that may or may not be similar). Thus, a first element,component, region, layer or section discussed below in one section ofthe specification (or claim) may be referred to as a second element,component, region, layer or section in another section of thespecification (or another claim).

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. As used herein, the term “and/or” includes any and allcombinations of one or more of the associated listed items and may beabbreviated as “/”. With the exception of “consisting of” and“essentially consisting of,” it will be further understood that alltransition terms describing elements of a step, component, device, etc.,are open ended. Thus, unless otherwise specified (e.g., with languagesuch as “only,” “without,” etc.), the terms “comprising,” “including,”“having,” etc., may specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

It will be understood that when an element is referred to as being“connected,” “coupled to” or “on” another element, it can be directlyconnected/coupled to/on the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, or as “contacting”or “in contact with” another element, there are no intervening elementspresent.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element's or feature's positional relationship relative toanother element(s) or feature(s) as illustrated in the figures. It willbe understood that such spatially relative terms are intended toencompass different orientations of the device in use or operation inaddition to the orientation depicted in the figures. Thus, a devicedepicted and/or described herein to have element A below element B, isstill deemed to have element A below element B no matter the orientationof the device in the real world.

Embodiments may be illustrated herein with idealized views (althoughrelative sizes may be exaggerated for clarity). It will be appreciatedthat actual implementation may vary from these exemplary views dependingon manufacturing technologies and/or tolerances. Therefore, descriptionsof certain features using terms such as “same,” “equal,” and geometricdescriptions such as “planar,” “coplanar,” “cylindrical,” “square,”etc., as used herein when referring to orientation, layout, location,shapes, sizes, amounts, or other measures, encompass acceptablevariations from exact identicality, including nearly identical layout,location, shapes, sizes, amounts, or other measures within acceptablevariations that may occur, for example, due to manufacturing processes.The term “substantially” may be used herein to emphasize this meaning,unless the context or other statements indicate otherwise.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill consistent with their meaning in the context of therelevant art and/or the present application.

FIG. 1 is a schematic block diagram of an extreme ultraviolet (EUV)exposure system 100 according to an example embodiment of the inventiveconcept.

Referring to FIG. 1, the exposure system 100 according to the presentexample embodiment may include a load-lock chamber 110, an EUV exposureapparatus 120, and an ultraviolet (UV) exposure apparatus 130.

The load-lock chamber 110 may function as a path for supplying a waferfrom a spinner 200 to the EUV exposure apparatus 120 and discharging thewafer from the EUV exposure apparatus 120 to the spinner 200. Theload-lock chamber 110 may be combined with an entrance and/or an exit ofan exposure chamber 124 of the EUV exposure apparatus 120, and anatmospheric pressure state and a vacuum state may be alternatelymaintained in the load-lock chamber 110. The wafer may be asemiconductor substrate on which an EUV photolithography process, forexample, EUV exposure, is performed to form a pattern. However, thewafer is not limited to the semiconductor substrate and may be any kindof substrate on which EUV exposure can be performed.

In the process of supplying and discharging the wafer through theload-lock chamber 110, the atmospheric pressure state may be maintainedin the load-lock chamber 110 and the wafer may be moved from the spinner200 to a chuck table 112 (of FIG. 5A) in the load-lock chamber 110 by aloading robot. Next, the atmospheric pressure state in the load-lockchamber 110 may be changed to a vacuum state by a vacuum pump, and thewafer may be moved to a chuck table 122 in the exposure chamber 124 by ascanner loading robot 145 (of FIG. 2). After EUV exposure is performedin the exposure chamber 124, the wafer may be moved to the load-lockchamber 110 in the vacuum state by the scanner loading robot 145. Next,the load-lock chamber 110 may be returned to the atmospheric pressurestate and the wafer may be moved to the spinner 200 again by anunloading robot.

As described in FIG. 1, the load-lock chamber 110 may include first andsecond load-lock chambers 110-1 and 110-2. The first load-lock chamber110-1 may be combined with the entrance of the exposure chamber 124 andthe second load-lock chamber 110-2 may be combined with the exit of theexposure chamber 124. Therefore, the wafer may be supplied to theexposure chamber 124 through the first load-lock chamber 110-1 and maybe discharged from the exposure chamber 124 to the spinner 200 throughthe second load-lock chamber 110-2. In certain embodiments, theload-lock chamber 110 may have a single body. For example, a load-lockchamber 110 may be connected to the exposure chamber 124 with a gatevalve between the load-lock chamber 110 and the exposure chamber 124. Awafer may be supplied to the exposure chamber 124 from the load-lockchamber 110 through a gate when the gate valve is open. The wafer may bedischarged from the exposure chamber 124 to the load-lock chamber 110through the gate when the gate valve is open. For example, the wafer maybe alternately supplied and discharged via the single load-lock chamber110.

For example, the spinner 200 may be an apparatus performing aphoto-resist (PR) coating process and a developing process on a wafer.The spinner 200 may be a track.

The EUV exposure apparatus 120 may perform EUV exposure on a wafer. Forexample, a wafer may have a top or upper surface, and a bottom or lowersurface opposite the top or upper surface. Semiconductor devices, e.g.,transistors, and/or circuitry may be formed on the upper or top surfaceof the wafer. For example, the EUV exposure may be performed on aphotoresist layer formed on the upper surface of a wafer. The EUVexposure apparatus 120 may include a chuck table 122, an EUV lightsource 121 (of FIG. 3), an optical system 125 (of FIG. 3), and an EUVmask 126 (of FIG. 3) in the exposure chamber 124. The EUV mask 126 maybe held by a mask holder included in a mask stage 127 of FIG. 3. FIG. 1illustrates only the exposure chamber 124 and the chuck table 122 forconvenience of illustration.

The chuck table 122 may include first and second chuck tables 122-1 and122-2. Each of the first and second chuck tables 122-1 and 122-2 maymove in an X direction, a Y direction, and/or a Z direction in an XYZcoordinate system. The first chuck table 122-1 may be used for actualexposure and the second chuck table 122-2 may be in a stand by state forexposure. However, since positions of the first and second chuck tables122-1 and 122-2 may be switched with each other, and/or the first andsecond chuck tables 122-1 and 122-2 receive wafers alternately, thefirst chuck table 122-1 may not be differentiated from the second chucktable 122-2. For example, the first chuck table 122-1 may be used for anexposure process of one wafer, and the second chuck table 122-2 may beused for an exposure process of another wafer. For example, the firstand second chuck tables 122-1 and 122-2 may be used alternately forexposure processes. The positions of the first and second chuck tables122-1 and 122-2 may be switched with each other during exposure ofmultiple wafers, and wafers may be loaded/unloaded to/from both of thefirst and second chuck tables 122-1 and 122-2. Therefore, EUV exposuremay be rapidly progressed. The number of the chuck tables in theexposure chamber 124 is not limited to 2. For example, the exposurechamber 124 may include one chuck table. Alternatively, the exposurechamber 124 may include three or more chuck tables.

In the operation of the EUV exposure apparatus 120, an EUV lightgenerated from the EUV light source 121 may be incident to the EUV mask126 (of FIG. 3) through an lighting system 125-1 (of FIG. 3) andreflected by the EUV mask 126, and may further irradiate a wafer 300 (ofFIG. 3) on the chuck table 122 through a projection system 125-2 (ofFIG. 3). A pattern of an EUV mask may be transferred to a PR on a waferthrough the exposure. For example, an EUV light reflected by an EUV maskmay irradiate a PR layer on a wafer with different intensity per regionaccording to a pattern of the EUV mask. For example, the PR may bedivided into an exposure area corresponding to higher intensity and anon-exposure area corresponding to lower intensity, and in the exposurearea, chemical characteristics of the PR may be greatly changed due toabsorbed light energy. For example, the PR in the exposure area maybecome soluble to a developer by the EUV light. In certain embodiments,the PR in the exposure area may be changed to be insoluble to adeveloper by the EUV light. Afterwards, a PR pattern may be formed byremoving the exposure area or the non-exposure area during a developingprocess according to the chemical characteristics of the PR.

The EUV exposure apparatus 120 may perform EUV exposure on a wafer. TheUV exposure apparatus 130 may perform UV exposure by irradiating a UVlight to the entire upper surface of a wafer without using a mask. Forexample, the UV exposure apparatus 130 may not have a mask holderconfigured to hold a photomask between a UV light source and a supportconfigured to support a substrate. For example, the support may be achuck table. The UV exposure on the entire upper surface of the wafermay also be referred to as UV flood exposure. The UV exposure of the UVexposure apparatus 130 may improve EUV exposure performance inpatterning the PR. For example, a PR formed on the upper surface of thewafer may be patterned better by performing the UV exposure on theentire upper surface of the wafer after the EUV exposure is performed.Improvement of the EUV exposure performance through the UV exposure onthe entire upper surface of the wafer will be described in detail withreference to FIGS. 8 and 9.

The UV exposure apparatus 130 may have various structures andcomponents. For example, the UV exposure apparatus 130 may be includedin the EUV exposure system 100 to perform the UV exposure in-situ withrespect to the entire upper surface of the wafer without a photomaskafter the EUV exposure is performed on the upper surface of the wafer.For example, a PR layer is formed on the entire upper surface of thewafer, and the PR layer is exposed to an EUV light through a photomask.After the EUV exposure, the PR layer is exposed to a UV light without aphotomask. The term “in-situ” indicates that the UV exposure on theentire upper surface is performed in a vacuum state. For example, thein-situ UV exposure may be performed in the exposure chamber 124 inwhich the EUV exposure is performed, without a break in the vacuumstate. In certain embodiments, the in-situ UV exposure may be performedin a load-lock chamber after the wafer is transferred from the exposurechamber 124 to the load-lock chamber 110, and before the wafer istransferred from the load-lock chamber 110 to a spinner 200 or another.For example, the UV exposure apparatus 130 may include a UV lamp and maybe combined with the EUV exposure apparatus 120 or the load-lock chamber110. In certain embodiments, the UV exposure apparatus 130 may have aseparate chamber structure from the load-lock chamber 110 and theexposure chamber 124, and may include a UV lamp and a chuck tabletherein. Based on the separate chamber structure, the UV exposureapparatus 130 may be combined with the EUV exposure apparatus 120 to bemaintained in a vacuum state when a wafer is moved from the EUV exposureapparatus 120 to the UV exposure apparatus 130.

An EUV exposure process in the EUV exposure system 100 according to thepresent example embodiment may progress in an order shown by bold arrowsin FIG. 1. For example, a wafer on which a PR is coated may betransferred from the spinner 200 to the first load-lock chamber 110-1and EUV exposure may be performed on the wafer after moving it to thechuck table 122 of the exposure chamber 124. When the EUV exposure iscompleted, the UV exposure may be performed on the entire top surface ofthe wafer in the UV exposure apparatus 130, and the wafer may betransferred to the spinner 200 for a developing process after beingtransferred to the second load-lock chamber 110-2. Regarding theload-lock chamber 110, an upper part with respect to a dashed line inFIG. 1 may be a space wherein a vacuum state is maintained and a lowerpart with respect to the dashed line may be a space wherein anatmospheric pressure state is maintained. For example, the dashed linecrossing the first and second load-lock chambers 110-1 and 110-2 mayrepresent that the first and second load-lock chambers 110-1 and 110-2may have two different pressure levels (e.g., atmosphere level and avacuum level) during an EUV exposure process. As described above, the UVexposure may be performed in-situ on the entire top surface of the waferwithout a photomask in the UV exposure apparatus 130 along with the EUVexposure with a photomask.

The EUV exposure system 100 according to the present example embodimentmay include a UV exposure apparatus capable of performing UV exposure onthe entire top surface of wafer. The EUV exposure system 100 accordingto the present example embodiment may improve EUV exposure performanceby performing UV exposure on the entire top surface of wafer on whichEUV exposure is performed. Therefore, a yield of an EUV exposure processmay be improved.

For example, the EUV exposure system 100 according to the presentexample embodiment may improve productivity of the EUV exposure system100 without degradation of a patterning quality. For example, the EUVexposure system 100 of the present embodiment may improve the quality ofpatterns or may maintain the quality of patterns at the same level asthe quality of patterns in existing EUV exposure systems. For example,the EUV exposure system 100 of the present embodiment uses less amountof EUV energy than that of the existing EUV exposure systems by virtueof the improvement of the EUV exposure performance. A reduction in thedose of EUV exposure may contribute to improvement of a process speed ofthe EUV exposure itself and UV exposure on the entire top surface of thewafer may be performed in-situ, and thus, the entire process time of theEUV exposure system 100 according to the present example embodiment maybe the same as or less than an exposure process of prior art. As aresult, in the EUV exposure system 100 according to the present exampleembodiment, throughput or productivity of the EUV exposure process maybe improved compared to that of an existing EUV exposure system whilemaintaining a better quality of PR patterns.

For example, an EUV light source power of currently implementable EUVexposure system may be up to about 80 W. To get a better productivity ofthe EUV exposure process than the one of, e.g., a DUV exposure system,the power of an EUV light source may need to be 500 W or more without UVflood exposure. Therefore, the competitiveness of mass production of theEUV exposure process compared to liquid immersion lithography is quitelimited. However, the EUV exposure system 100 according to the presentexample embodiment may produce an acceptable or a higher level ofpatterning quality. The present embodiment may also enhance theproductivity of the EUV exposure process by performing EUV exposure atlow power together with UV exposure at high power.

FIG. 2 is an exemplary schematic view of the EUV exposure system 100 ofFIG. 1, according to an example embodiment of the inventive concept. InFIG. 2, like reference numerals in FIG. 1 denote like elements, andrepeated descriptions thereof are omitted.

Referring to FIG. 2, an EUV exposure system 100 a according to thepresent example embodiment may include a load-lock chamber 110, an EUVexposure apparatus 120, a UV exposure apparatus 130, and a waferexchange chamber 140. The load-lock chamber 110 and the EUV exposureapparatus 120 are as described in FIG. 1. For example, the load-lockchamber 110 may include the first and second load-lock chambers 110-1and 110-2, and the EUV exposure apparatus 120 may include the first andsecond chuck tables 122-1 and 122-2 in the exposure chamber 124.

Dashed circles in FIG. 2 show positions where a wafer is disposed. Gatevalves 102 to 106 may be disposed in chambers corresponding to entrancesand/or exits, respectively. For example, the input gate valve 102 andthe output gate valve 104 may be disposed in the first load-lock chamber110-1. The input gate valve 105 and the output gate valve 103 may bedisposed in the second load-lock chamber 110-2. The input/output gatevalve 106 may be disposed in the exposure chamber 124. The spinner 200may be combined with the input gate valve 102 of the first load-lockchamber 110-1 and the output gate valve 103 of the second load-lockchamber 110-2.

The wafer exchange chamber 140 may be combined with the first load-lockchamber 110-1 through the output gate valve 104, be combined with thesecond load-lock chamber 110-2 through the input gate valve 105, and becombined with the exposure chamber 124 through the input/output gatevalve 106. The wafer exchange chamber 140 may include a robot 145 formoving a wafer. The robot 145 may be used in a vacuum state and may havedual ends. For example, the robot 145 may include a holding arm havingtwo wafer loaders opposite each other, and each of the two wafer holdersmay have two branches as shown in FIG. 2. However, a structure of therobot 145 is not limited thereto. For example, the robot 145 may have asingle end, e.g., one wafer loader. In certain embodiments, othercarriers may be used instead of the robot 145.

The robot 145 may transfer a wafer from the first load-lock chamber110-1 to the second chuck table 122-2 in a stand-by mode in the exposurechamber 124. For example, the stand-by mode is a waiting state whileanother wafer is subject to EUV exposure loaded on the first chuck table122-1. The robot 145 may transfer a wafer on which EUV exposure has beenperformed from the exposure chamber 124 to the second load-lock chamber110-2. In certain embodiments, the UV exposure apparatus 130 may bedisposed in the exposure chamber 124. When the UV exposure apparatus 130is disposed in the exposure chamber 124, the robot 145 may transfer awafer that is exposed to EUV with a photomask, and to UV without aphotomask on the entire top surface, from the exposure chamber 124 tothe second load-lock chamber 110-2.

A wafer alignment may be performed by an alignment unit in the firstload-lock chamber 110-1 before a wafer is transferred from the firstload-lock chamber 110-1 to the second chuck table 122-2. For example,the wafer may be repositioned on the robot 145 before the wafer istransferred to the second chuck table 122-2 from the first load-lockchamber 110-1.

The UV exposure apparatus 130 may include a UV lamp 132 generating andoutputting a UV light, and the UV lamp 132 may be disposed in theexposure chamber 124 or in the second load-lock chamber 110-2 asindicated by a bold arrow in FIG. 2. In certain embodiments, the UVexposure apparatus 130 includes at least two lamps generating lightshaving different wavelengths. For example, the at least two lamps may beused simultaneously or alternately. The structure of disposing the UVlamp 132 in the exposure chamber 124 will be described in detail withreference to FIGS. 3 and 4, and the structure of disposing the UV lamp132 in the second load-lock chamber 110-2 will be described in detailwith reference to FIGS. 5A to 6.

When the UV lamp 132 is disposed in the exposure chamber 124, EUVexposure may be performed on a wafer in the exposure chamber 124 and theUV exposure on the entire upper surface may be performed on the wafer bythe UV lamp 132. Next, the wafer may be transferred to the secondload-lock chamber 110-2 by the robot 145. When the UV lamp 132 isdisposed in the second load-lock chamber 110-2, EUV exposure may beperformed on a wafer in the exposure chamber 124 and the wafer may betransferred to the second load-lock chamber 110-2 by the robot 145.Next, the UV exposure on the entire upper surface may be performed onthe wafer by the UV lamp 132 in the second load-lock chamber 110-2.

In the EUV exposure system 100 a according to the present exampleembodiment, the UV exposure apparatus 130 may include the UV lamp 132.For example, the UV lamp 132 may be disposed in the exposure chamber 124or may be combined with the second load-lock chamber 110-2. For example,the EUV exposure system 100 a according to the present exampleembodiment may perform the UV exposure on the entire upper surface ofwafer in-situ after EUV exposure. As described above, the total time ofan EUV exposure process (the EUV exposure and the UV exposure on theentire upper surface) may increase due to addition of the UV exposure onthe entire upper surface. However, an EUV exposure time itself may bereduced because the UV exposure on the entire upper surface is performedin-situ and EUV exposure performance is improved. Therefore, the totaltime of the EUV exposure process in the EUV exposure system 100 a may bemaintained or reduced compared to an existing EUV exposure system.

FIG. 3 is a schematic diagram of an example embodiment of forming the UVexposure apparatus 130 in the EUV exposure apparatus 120, in the EUVexposure system 100 a of FIG. 2 according to an example embodiment ofthe inventive concept, and FIG. 4 is a detailed perspective view of theUV exposure apparatus 130 of FIG. 3.

Referring to FIGS. 3 and 4, the EUV exposure apparatus 120 may includethe EUV light source 121, the chuck table 122, the optical system 125,and the EUV mask 126 in the exposure chamber 124.

The EUV light source 121 may generate a light within a wavelength rangeof an EUV light, for example, about 100 nm or less. The wavelength ofthe EUV light generated from the EUV light source 121 may be adjusted,e.g., by filtering, to an operating wavelength of the projection system125-2, for example, 13.5 nm or 7 nm. In certain embodiments, the EUVlight source 121 may be adjusted to generate a proper wavelength for theprojection system 125-2 to use. For example, the EUV light source 121may be configured to generate a proper wavelength for the projectionsystem 125-2 to use, e.g., 13.5 nm or 7 nm. For example, a plasma lightsource or synchrotron light source may be used as the EUV light source121. The plasma light source may be a laser-produced plasma (LPP) lightsource including tin (Sn) as a target and may use a CO2 laser as anexcitation light source. As described above, power of the EUV lightsource 121 may be considerably less than that of an existing UV lightsource. For example, power of the EUV light source 121 may be about 80W.

EUV exposure may be performed on a wafer 300 on the chuck table 122. Thesecond chuck table 122-2 in a stand-by mode is not shown in FIG. 3, anda chuck table 122-1′ under the UV lamp 132, which is the first chucktable 122-1 used for the EUV exposure, may move its position from underthe projection system 125-2 to under the UV lamp 132 as indicated by ablack arrow.

In the optical system 125, an EUV light generated from the EUV lightsource 121 may be incident to the EUV mask 126, and may irradiate thewafer 300 with an EUV light reflected by the EUV mask 126. The opticalsystem 125 may include the lighting system 125-1 and the projectionsystem 125-2.

The lighting system 125-1 may include a plurality of lighting mirrorsand may irradiate the EUV mask 126 with the EUV light generated from theEUV light source 121. Since a structure of the lighting system 125-1including a plurality of lighting mirrors is well-known to those ofordinary skill in the art, only a first lighting mirror 123 collectingEUV light generated from the EUV light source 121 and supplying the EUVlight to another lighting mirror is illustrated and the other lightingmirrors are not shown as included in a square block of the lightingsystem 125-1 for convenience of descriptions.

The projection system 125-2 may irradiate the wafer 300 with the EUVlight reflected by the EUV mask 126. Since a structure of the projectionsystem 125-2 including a plurality of imaging mirrors is well-known tothose of ordinary skill in the art, the imaging mirrors are not shown asincluded in a square block for convenience of descriptions.

The EUV mask 126 may be disposed on a mask stage 127. Although not shownin FIG. 3, a slit may be disposed under the EUV mask 126. The slit maypartially limit EUV light from irradiating the EUV mask 126, andtherefore, only a partial region of the EUV mask 126 is irradiated withthe EUV light, e.g., in a region that the EUV light passes through theslit. The mask stage 127 may move in a direction opposite to a scanningdirection during a scanning process, and the EUV light may irradiate acorresponding region of the EUV mask 126 while moving through the slit.

As illustrated in FIG. 3, the UV exposure apparatus 130 may include theUV lamp 132 disposed in the exposure chamber 124. UV exposure may beperformed on the upper surface of the wafer 300 on which EUV exposurehas been performed by using the UV lamp 132. The UV lamp 132 maygenerate and output a light within a wavelength of UV light. Forexample, the UV lamp 132 may be a mercury lamp, and may generate andoutput an I-line light with a wavelength of about 365 nm. The UV lamp132 may have high output power of 500 W or more. For example, the UVexposure on the entire upper surface of the wafer 300 may be performedby using the UV lamp 132 having high output power of 500 W or more andmay contribute to improvement of EUV exposure performance.

In FIG. 4, the UV lamp 132 illustrated as a cylinder shape is simplifiedto correspond to a shape of the wafer 300 However, the UV lamp 132 mayinclude a complicated structure to generate a UV light. The UV lamp 132may have various shapes besides the cylinder shape as long as a UV lightis irradiated to the entire upper surface of the wafer 300.

In the present embodiment, the UV exposure on the entire upper surfaceis mainly described to be performed after the EUV exposure is performedin the EUV exposure systems, but the exposure after the EUV exposure isnot limited to the UV exposure on the entire upper surface. In certainembodiments, deep UV (DUV) exposure may be performed on the entire uppersurface after EUV exposure. A DUV lamp generating a light within awavelength of a DUV light, for example, a KrF laser (248 nm) lamp, anArF laser (193 nm) lamp, or an F2 laser (157 nm) lamp may be used forthe DUV exposure. Whether to perform UV exposure or DUV exposure on theentire upper surface after EUV exposure may depend on characteristics ofa PR formed on the wafer 300. For example, EUV exposure performance maybe maximized by UV exposure or DUV exposure depending on chemicalcomponents of a PR. Therefore, UV exposure or DUV exposure on the entireupper surface may be appropriately selected depending on a chemicalcomponent of a PR. In certain embodiments, a UV exposure apparatus 130may include a UV lamp together with a DUV lamp, and thus, mayselectively perform UV exposure or DUV exposure on the entire uppersurface by selecting corresponding lamps.

Hereinafter, a UV exposure apparatus or UV exposure on the entire uppersurface without a photomask will be described in detail. However, a DUVexposure apparatus or DUV exposure on the entire upper surface without aphotomask may also be applied to the EUV exposure system instead of theUV exposure apparatus or the UV exposure unless otherwise described.

FIGS. 5A and 5B are respectively a schematic cross-sectional view and aschematic plan view of an example embodiment of forming the UV exposureapparatus in a load-lock chamber in the EUV exposure system 100 a ofFIG. 2 according to an example embodiment of the inventive concept.

Referring to FIGS. 5A and 5B, in the EUV exposure system according tothe present example embodiment, the UV exposure apparatus 130 may bedisposed outside or on a cover of the second load-lock chamber 110-2.For example, the input gate valve 105 and the output gate valve 103 maybe respectively disposed on both side surfaces of the chamber cover orexternal wall 114 in the second load-lock chamber 110-2. The wafer 300may be supplied to the second load-lock chamber 110-2 through the inputgate valve 105 and may be discharged to outside through the output gatevalve 103. The wafer 300 may have been exposed to EUV in the EUVexposure apparatus 120 (of FIG. 2 or FIG. 3) before the wafer 300 isexposed to the UV in the second load-lock chamber 110-2.

A chuck table 112 may be disposed in the second load-lock chamber 110-2and the wafer 300 may be disposed on the chuck table 112. A pipe 118connected to a vacuum pump may be disposed under a lower plate of thechamber cover or external wall 114. The inside of the second load-lockchamber 110-2 may be changed to a vacuum state when the vacuum pumpdischarges air from the second load-lock chamber 110-2 to outsidethrough the pipe 118.

A transparent window 116 may be disposed on an upper plate of thechamber cover or external wall 114. For example, an upper portion of thechamber cover 114 may be formed of a transparent window 116. The upperplate of the chamber cover or external wall 114 and the transparentwindow 116 may form an upper cover of the second load-lock chamber110-2. The transparent window 116 may include a material transmittinglight, for example, a UV light.

The UV lamp 132 of the UV exposure apparatus 130 may be outside thesecond load-lock chamber 110-2. For example, the UV lamp 132 may bedisposed on an outer surface of the upper plate of the chamber cover orexternal wall 114, e.g., on a position where the transparent window 116is located. Therefore, a UV light of the UV lamp 132 may irradiate theentire upper surface of the wafer 300 after passing through thetransparent window 116.

FIG. 5B is a plan view of the second load-lock chamber 110-2, andillustrates relative sizes of the UV lamp 132 on the upper plate of thechamber cover or external wall 114 and the transparent window 116 underthe UV lamp 132. For example, a horizontal cross-sectional area of theUV lamp 132 may be greater than that of the transparent window 116.However, the inventive concept is not limited thereto and the horizontalcross-sectional area of the transparent window 116 may be greater thanthat of the UV lamp 132. For example, horizontal cross-sectional shapesof the transparent window 116 and the UV lamp 132 are not limited to acircular shape, and may have various shapes such as a square shape or anoval shape.

For example, a vacuum state may be maintained in the second load-lockchamber 110-2 when the UV exposure is performed on the entire uppersurface of the wafer 300 by using the UV exposure apparatus 130. Forexample, the UV exposure on the entire upper surface may be performedin-situ. After this, the second load-lock chamber 110-2 may be providedwith a gas to become an atmospheric pressure state and the wafer 300 maybe transferred to the spinner 200 (of FIG. 2).

FIG. 6 is a schematic cross-sectional view of an example embodiment ofinstalling the UV exposure apparatus 130 in the load-lock chamber 110,in the EUV exposure system 100 a of FIG. 2 according to an exampleembodiment of the inventive concept. In FIG. 6, like reference numeralsin FIGS. 5A and 5B denote like elements, and repeated descriptionsthereof are omitted.

Referring to FIG. 6, in the EUV exposure system according to the presentexample embodiment, the UV exposure apparatus 130 may be disposed in thesecond load-lock chamber 110-2. For example, the UV lamp 132 of the UVexposure apparatus 130 may be arranged on an inner surface of the upperplate of the chamber cover or external wall 114. Since the UV lamp 132is disposed in the second load-lock chamber 110-2, a transparent windowmay not be disposed on the upper plate of the chamber cover or externalwall 114. For example, the whole area of the upper cover of theload-lock chamber 110-2 may be opaque.

In the EUV exposure system according to the present example embodiment,the UV exposure on the entire upper surface of the wafer 300 by usingthe UV exposure apparatus 130 may be performed in-situ. For example, avacuum state may be maintained in the second load-lock chamber 110-2during the UV exposure.

FIG. 7 is an exemplary schematic view of the EUV exposure system 100 ofFIG. 1, according to an example embodiment of the inventive concept. InFIG. 7, like reference numerals in FIG. 2 denote like elements, andrepeated descriptions thereof are omitted.

Referring to FIG. 7, an EUV exposure system 100 b according to thepresent example embodiment may be different from the EUV exposure system100 a of FIG. 2 in that a UV exposure apparatus 130 a is formed to be ofa separate chamber type. For example, the UV exposure apparatus 130 amay include a UV chamber 134, a chuck table (not shown), and a UV lamp132. The UV lamp 132 may be disposed inside or outside the UV chamber134. When the UV lamp 132 is disposed outside, a transparent window maybe disposed on an upper plate or cover of the UV chamber 134.

When the UV exposure is performed in the UV exposure apparatus 130 a, avacuum state may be maintained in the UV chamber 134. Since the insideof the wafer exchange chamber 140 generally is maintained a vacuumstate, the UV exposure apparatus 130 a may be combined with the waferexchange chamber 140, in which the UV chamber 134 is open toward thewafer exchange chamber 140 without a gate valve. However, in certainembodiments, the UV exposure apparatus 130 a may be combined with thewafer exchange chamber 140 through a gate valve and a separate vacuumstate may be obtained in the UV exposure apparatus 130 a by using avacuum pump.

A wafer on which EUV exposure has been performed may be transferred fromthe exposure chamber 124 to the UV chamber 134, and the UV exposure onthe entire upper surface of the wafer may be performed without aphotomask in the UV chamber 134. The wafer on which the UV exposure hasbeen performed may be transferred to the second load-lock chamber 110-2.For example, the wafer may be transferred by the robot 145.

So far, example embodiments of disposing the UV exposure apparatuses 130and 130 a in the exposure chamber 124 or the second load-lock chamber110-2, or of using a separate chamber type have been described. However,a location or a structure of disposing a UV exposure apparatus is notlimited thereto. For example, in the EUV exposure system according tothe present example embodiment, a UV exposure apparatus may be disposedin various parts of the EUV exposure system with various structures aslong as UV exposure is performed on a wafer in-situ after EUV exposure.For example, if a sufficient space is available in the wafer exchangechamber 140, a UV exposure apparatus may be realized by including achuck table and a UV lamp in the wafer exchange chamber 140. In thepresent embodiment, a separate chamber may not be used to realize a UVexposure apparatus in the exposure chamber 124 or the second load-lockchamber 110-2. A chuck table for supporting a wafer may be included inthe wafer exchange chamber 140 to realize a UV exposure apparatus in thewafer exchange chamber 140.

FIG. 8 is a graph illustrating a principle of improving the exposureperformance of EUV exposure systems according to example embodiments ofthe inventive concept, wherein an x-axis indicates an exposure area EAand a non-exposure area NEA of a PR on a wafer, and a y-axis indicatesthe amount of energy absorbed by the PR and that a unit thereof may bean arbitrary unit. Here, E1 may be a graph of energy absorbed in the PRafter EUV exposure is performed, and E2 may be a graph of energyabsorbed in the PR on which UV exposure on the entire upper surface isperformed after EUV exposure is performed.

Referring to FIG. 8, in the graph E1, a difference is not great betweenthe energy absorbed in an exposure area EA of the PR and the energyabsorbed in a non-exposure area NEA of the PR after EUV exposure isperformed. The exposure area EA may be an area to which an EUV lightwith a high intensity is irradiated and the non-exposure area NEA may bean area to which an EUV light is not irradiated or an EUV light with alow intensity is irradiated. For example, the energy absorbed in the PRmay be used to change chemical characteristics of the PR. For example,when the PR is a positive resist material including a photo acidgenerator (PAG), an acid may be generated from the PAG by irradiatinglight thereon, and an area to which light is irradiated, that is, theexposure area EA may change its chemical characteristics toalkali-soluble characteristics by acid action. Afterwards, the exposurearea EA may be removed through an alkali developing solution during adeveloping process.

For example, the more obvious a difference between chemicalcharacteristics of the exposure area EA and that of the non-exposurearea NEA is, the better PR patterning in the developing process is. Forexample, the PR patterning quality may depend on the degrees of reactionbetween irradiated light energy and the PR in the exposure area EA andthe non-exposure area. Therefore, the greater a difference betweenchemical characteristics of the exposure area EA and that of thenon-exposure area NEA is by an exposure process, the better exposureperformance may be. The difference of chemical characteristics betweenthe exposure area EA and the non-exposure area NEA may depend on anamount of absorbed light energy during the exposure process. As shown inFIG. 8, in a case of EUV exposure, a difference between the energyabsorbed in the exposure area EA and the energy absorbed in thenon-exposure area NEA may not be great. Therefore, the difference ofchemical characteristics may not be great and exposure performance maynot be good. The low exposure performance of EUV exposure may be due tolow output power of an EUV light source.

E2 in FIG. 8 shows that the difference is great between the energyabsorbed in the exposure area EA and the energy absorbed in thenon-exposure area NEA of the PR on which the UV exposure on the entireupper surface of the wafer is performed after EUV exposure is performed.An increase in the difference of the absorbed energy may result in anincrease in the difference of the chemical characteristics, and thus,may contribute to improvement of exposure performance of an EUV exposureprocess.

Although an accurate mechanism of a remarkable increment of energyabsorption in the exposure area EA during the UV exposure process on theentire upper surface of a wafer after EUV exposure is performed is notclear, it is verified experimentally, and it is presumed that energyabsorption is accelerated in a region where chemical characteristics arechanged by an EUV light and a change in chemical characteristics isamplified by the UV exposure.

FIG. 9 is a graph for comparing the exposure performance of EUV exposuresystems according to example embodiments of the inventive concept withthat of an existing EUV exposure system, wherein an x-axis indicatesdoses of EUV light and that a unit thereof may be an arbitrary unit, anda y-axis indicates line widths of patterns and that a unit thereof maybe nm. “Single” indicates a graph that EUV exposure is performed withouta UV exposure, and “I-line 1” and “I-line 2” indicate graphs that UVexposure is performed with a first UV dose and a second UV dose alongwith the EUV exposure, respectively. The second UV dose may be ten timesor greater than the first UV dose.

Referring to FIG. 9, performing UV exposure on the entire upper surfaceafter EUV exposure (I-line 1 and I-line 2) may reduce an EUV dose toproduce the same patterns as an EUV-only exposure process (single inFIG. 9) does. For example, when a line width of 19 nm is realized andEUV exposure is performed (Single), an EUV dose of about 38 may be used.Also, an EUV dose of about 36 may be used when UV exposure on the entiresurface is performed together with the first UV dose (I-line 1), and anEUV dose of about 31 may be used when UV exposure on the entire surfaceis performed together with the second UV dose (I-line 2). Therefore, asame patterning quality may be obtained with a smaller EUV dose byperforming UV exposure on the entire upper surface after EUV exposure.For example, a finer pattern may be realized with the same EUV dose beadding UV exposure on the entire upper surface after EUV exposure.

A dose may be expressed as J/cm² or mJ/cm² in an exposure process, andmay be converted to length of time. For example, if 100 mJ/cm² of EUVlight energy is used to expose a wafer, it may take 100 msec, and if1000 mJ/cm² of EUV light energy is used to expose a wafer, it may take1000 msec. Therefore, as a smaller dose of EUV energy is used for anexposure, the corresponding process time may be reduced. As a result, byperforming an additional UV exposure, an EUV exposure processing timemay be reduced while maintaining a patterning quality at the same levelas the process performing EUV-only exposure (Single in FIG. 9).

An exposure processing time may be increased by adding an UV exposureprocess on the entire upper surface after an EUV exposure. In thepresent embodiment, because the EUV exposure time itself may be reduced,the total time (a sum of an EUV exposure time and an UV exposure time)of the EUV exposure process may not be increased. In certainembodiments, a wafer is exposed to UV by the UV exposure apparatus 130while another wafer is exposed to EUV by the EUV exposure apparatus 120.Therefore, the exposure processing time may be reduced. For example, theEUV exposure process according to the present example embodiment mayimprove exposure performance while maintaining a patterning quality.Therefore, production of the EUV exposure process may be increased.

FIG. 10 is a flowchart of an EUV photolithography process according toan example embodiment of the inventive concept. FIG. 10 is describedwith reference to FIG. 1 or FIG. 2 and repeated descriptions thereof areomitted for convenience of description.

Referring to FIG. 10, in operation S110, a PR layer is coated on awafer. The PR coating may be performed by, for example, the spinner 200.The wafer may be a pure semiconductor wafer or may be a semiconductorwafer on which a predetermined material layer is formed. After the PRcoating on the wafer is completed, the wafer may be transferred to theEUV exposure apparatus 120 via the load-lock chamber 110.

In operation S120, the EUV exposure apparatus 120 may perform EUVexposure on the wafer. The EUV exposure operation may be performed bymaking an EUV light of the EUV light source 121 (of FIG. 3) incident onthe EUV mask 126 through the lighting system 125-1 (of FIG. 3) andirradiating the upper surface of the wafer with the EUV light reflectedby the EUV mask 126 and transferring through the projection system 125-2(of FIG. 3).

In operation S130, the UV exposure apparatus 130 may perform UV exposureon the entire upper surface of the wafer on which EUV exposure has beenperformed. As described above, the UV exposure apparatus 130 may bedisposed in the exposure chamber 124 or the second load-lock chamber110-2 in a form of including only the UV lamp 132 or in a form ofincluding the UV lamp 132 and a chuck table in a separate chamber asdescribed above. The UV exposure on the entire upper surface of thewafer may be performed with the EUV exposure in-situ. After the UVexposure on the entire upper surface of the wafer is completed, thewafer may be transferred to the spinner 200 via the load-lock chamber110-2.

In operation S140, the spinner 200 may perform a developing process ofthe PR layer. A pattern may be formed with the PR layer on the waferthrough the developing process. Although not shown in FIG. 10, the EUVphotolithography process may further include a cleaning process and abaking process after the developing process.

Dashed lines distinguish the EUV exposure and the UV exposure on theentire upper surface performed in the EUV exposure systems 100 and 100 afrom the PR coating process and the developing process performed in thespinner 200, wherein the EUV exposure systems 100 and 100 a are eachrepresented as a scanner for the sake of convenience. Therefore, thepresent embodiment should not be limited by the scanner. For example, astepper or another may be used for the EUV exposure process.

FIG. 11 is a flowchart of a process of manufacturing a semiconductordevice including EUV photolithography exposure according to an exampleembodiment of the inventive concept. In FIG. 11, like reference numeralsin FIG. 10 denote like elements, and repeated descriptions thereof areomitted.

Referring to FIG. 11, an EUV photolithography process may be performedby progressing from a PR coating operation (S210) to a developingoperation (S240) as described in regard to FIG. 10 above.

In operation S250, a subsequent semiconductor process may be performedon a wafer. The subsequent semiconductor process may include variousprocesses. For example, the subsequent semiconductor process may includea process of etching a lower material layer of the wafer by using a PRpattern obtained through the EUV photolithography process describedabove. The subsequent semiconductor process may include a depositionprocess, an etching process, an ion process, and/or a cleaning process.The etching process may use the EUV photolithography process or otherphotolithography processes. The etching process may be performed withouta separate photolithography process. Integrated circuits and wirings fora corresponding semiconductor device may be formed by performing thesubsequent semiconductor process. The subsequent semiconductor processmay include a test process for a semiconductor device at a wafer level.

In operation S260, after the subsequent semiconductor process, the wafermay be individualized into each of semiconductor chips. Theindividualization of the wafer into each of semiconductor chips may beperformed through a sawing process by using a blade or a laser.

In operation S270, a packaging process for the semiconductor chips maybe performed. The packaging process may be a process of mounting thesemiconductor chips on a printed circuit board (PCB) and sealing thesemiconductor chips with a sealing member. The packaging process mayinclude a process of stacking a plurality of semiconductors on the PCBin multiple layers and forming a stack package, or a process of stackinga stack package on the stack package and forming a package-on-package(POP) structure. A semiconductor device or a semiconductor package maybe completed through the packaging process for the semiconductor chips.Additionally, a test process for the semiconductor package may beperformed after the packaging process.

While the inventive concept has been particularly shown and describedwith reference to example embodiments thereof, it will be understoodthat various changes in form and details may be made therein withoutdeparting from the spirit of the description and scope of the inventionshould be determined by the following claims.

What is claimed is:
 1. An EUV exposure system comprising: an extremeultraviolet (EUV) exposure apparatus configured to perform EUV exposureon a wafer disposed on a chuck table; a first load-lock chamber combinedwith the EUV exposure apparatus and configured to supply and dischargethe wafer to/from the EUV exposure apparatus; and an ultraviolet (UV)exposure apparatus configured to perform UV exposure by irradiating a UVlight to an entire upper surface of the wafer, wherein the UV exposureapparatus does not include a mask holder.
 2. The EUV exposure system ofclaim 1, wherein the UV exposure apparatus is disposed in the EUVexposure apparatus so that the UV exposure is performed in-situ afterthe EUV exposure.
 3. The EUV exposure system of claim 1, wherein the UVexposure apparatus is disposed in the EUV exposure apparatus or thefirst load-lock chamber.
 4. The EUV exposure system of claim 1, whereinthe UV exposure apparatus comprises a UV lamp configured to generate theUV light, and the UV lamp is disposed in the EUV exposure apparatus. 5.The EUV exposure system of claim 1, wherein the UV exposure apparatuscomprises a UV lamp configured to generate the UV light, and the UV lampis disposed inside or outside the first load-lock chamber.
 6. The EUVexposure system of claim 1, further comprising a second load-lockchamber, wherein the first load-lock chamber is configured to dischargethe wafer from the EUV exposure apparatus and the second load-lockchamber is configured to supply the wafer to the EUV exposure apparatus,and the UV exposure apparatus is disposed in the first load-lockchamber.
 7. The EUV exposure system of claim 6, wherein the UV exposureapparatus comprises a UV lamp configured to generate the UV light,wherein the first load-lock chamber comprises a transparent windowformed on an upper cover of the first load-lock chamber, the transparentwindow configured to transmit the UV light, wherein the UV lamp isdisposed on an upper portion of the transparent window outside the firstload-lock chamber, and the UV lamp is configured to irradiate the waferdisposed inside the second load-lock chamber with the UV light after theUV light passes through the transparent window.
 8. The EUV exposuresystem of claim 1, wherein the UV exposure apparatus comprises at leasttwo lamps configured to generate lights having different wavelengths. 9.The EUV exposure system of claim 1, wherein the UV exposure apparatuscomprises at least one of a UV lamp configured to generate an I-linelight and a deep UV (DUV) lamp configured to generate a DUV light. 10.The EUV exposure system of claim 1, wherein the EUV exposure apparatuscomprises an EUV lamp configured to generate an EUV light, an EUV maskcomprising a pattern configured to be transferred to the wafer, anoptical system configured to transmit the EUV light generated from theEUV lamp to the EUV mask and further configured to transmit the EUVlight reflected by the EUV mask to the wafer disposed on the chucktable, the UV exposure apparatus comprises a UV lamp disposed in the EUVexposure apparatus, and the chuck table is one of at least two chucktables and at least one of the chuck tables is configured to betransferred to a location corresponding to the UV lamp.
 11. An EUVexposure system comprising: an extreme ultraviolet (EUV) exposureapparatus configured to perform EUV exposure on a wafer disposed on achuck table; a first load-lock chamber combined with the EUV exposureapparatus and configured to supply the wafer into the EUV exposureapparatus; a second load-lock chamber combined with the EUV exposureapparatus and configured to discharge the wafer from the EUV exposureapparatus to outside of the EUV exposure apparatus; and a UV exposureapparatus disposed in the EUV exposure apparatus or the second load-lockchamber and configured to perform UV exposure on the wafer.
 12. The EUVexposure system of claim 11, wherein the UV exposure apparatus isconfigured to perform UV exposure by irradiating a UV light to an entireupper surface of the wafer without using a mask.
 13. The EUV exposuresystem of claim 11, wherein the UV exposure apparatus comprises a UVlamp configured to generate a UV light, an upper cover of the secondload-lock chamber comprises a transparent window capable of transmittingthe UV light, the UV lamp is disposed on an upper portion of thetransparent window outside the second load-lock chamber, and the UV lampis configured to irradiate the wafer with the UV light while the waferis disposed inside the second load-lock chamber.
 14. The EUV exposuresystem of claim 11, wherein the UV exposure apparatus is disposed in theEUV exposure apparatus, and the UV exposure apparatus is configured toperform the UV exposure on the entire upper surface of the wafer afterthe EUV exposure is performed on the upper surface of the wafer with aphotomask.
 15. The EUV exposure system of claim 11, wherein the UVexposure apparatus comprises at least one of a UV lamp configured togenerate an I-line light and a deep UV (DUV) lamp configured to generatea DUV light, and the UV exposure apparatus is configured to perform theUV exposure on the entire upper surface of the wafer via the UV lamp orthe DUV lamp.
 16. An apparatus comprising: an EUV exposure chambercomprising a chuck table, an extreme ultraviolet (EUV) light sourceconfigured to emit EUV light and a mask holder being positioned betweenthe EUV light source and the chuck table; and an ultraviolet (UV) lightsource configured to emit UV light, wherein the EUV light source ispositioned to expose a photoresist (PR) layer coated on a wafer to anEUV light emitted from the EUV light source that is transferred via aphotomask held by the mask holder, and wherein the UV light source isconfigured to expose the PR layer to a UV light emitted from the UVlight source without using a photomask after the PR layer is exposed tothe EUV light.
 17. The apparatus of claim 16, further comprising: aload-lock chamber connected to the EUV exposure chamber by a gate valve,wherein the load-lock chamber is configured such that PR layer isexposed to the UV light within the load-lock chamber; and wherein thegate valve is configured to isolate a vacuum inside the EUV exposurechamber from an atmospheric pressure in the load-lock chamber.
 18. Theapparatus of claim 17, wherein the EUV exposure and the UV exposure areperformed in a vacuum state.
 19. The apparatus of claim 16, wherein theUV light is a deep UV (DUV) light.
 20. The apparatus of claim 16,wherein the EUV exposure chamber is configured such that the PR layer isexposed to the UV light within the EUV exposure chamber.